1. Field of the Invention
The present invention relates to apparatus for assembling shade devices for insulating a building area such as a window or wall against heat transmission. More specifically, the apparatus relates to apparatus for assembling a shade device such as that described in U.S. Pat. Nos. 4,039,019 (Hopper) and 4,194,550 (Hopper) in an efficient economical way on a mass production basis.
Great concern has arisen in recent years for the increased and inefficient use of energy. Such use is particularly troublesome because most energy presently is derived from finite fossil fuels. Accordingly, proposals have been made to more efficiently use energy through conservation. One such proposal is for a multilayer insulating window shade device that significantly reduces the transmission of radiant, convective, and conductive heat through building areas such as windows. This device is described in U.S. Pat. Nos. 4,039,019 and 4,194,550, both granted to the applicant here and includes a plurality of shade sheets attached to a roller to be retracted thereon and detracted therefrom. The sheets are provided with a surface having a low emittance. Spacer devices are mounted with one sheet of each pair of adjacent sheets to space them apart when detracted from the roller. Each spacer device comprises an elongated strip of sheet material having a major axis and a normally arcuate cross-sectional shape curved about the major axis. When the multilayer shade device is drawn from the roller to cover the building area to be insulated, adjacent sheets are therefore spaced apart to define dead air spaces. These dead air spaces, in combination with the low surface emittance provided by the surfaces of the individual shade sheets, yield a synergistic insulating effect to resist radiant, conductive, and convective heat transmission. That is the insulating valve of the drawn shade substantially exceeds the sum of the insulating valves of a single sheet having a low emittance surface and of a spaced pair of sheets neither of which has a low emittance surface.
Because the shade device does not itself supply energy, it may be considered a passive energy conservation device. In winter months during periods of high transmission of heat energy inwardly through a window, the shade may be retracted onto its roller to allow the interior of the building to be warmed by available sunlight. However, when unwanted heat transmission occurs outwardly through the window, the shade may be drawn to minimize such waste. Conversely, in summer months the shade may be drawn during the day to limit heat transmission into a building area and opened at night to allow unwanted heat to escape. Therefore, this multilayer insulating window shade device provides highly desirable results in conservation of limited fuels used for space heating and cooling.
2. Description of the Prior Art
Various proposals have been made for assembling insulating shade devices such as those described above. For example, in the past, a single sheet has been spread on a table and a single spacer device has been temporarily mounted thereon. Typically, the material from which the shade sheet and spacer device are made are heat weldable. Therefore, the sheet and spacer device were feed to a single pair of reciprocally mounted heat welding bars that clamp and heat weld one edge of the spacer device to the single sheet so that the opposite longitudinal edge of the spacer device curves away from and is spaced from the sheet. This process is repeated until a sufficient number of spacer devices have been mounted on the single sheet. A second sheet is then assembled in the same way and is in turn assembled with the first completed sheet. This process is continued until a shade device has been assembled with as many sheets as desired. The multiple sheets may then be secured to a roller to be retracted thereon.
It is apparent that the procedure for assembling the shade device described above is time consuming and therefore inefficient and uneconomical. Accordingly, it is desirable to provide for automatic assembly of the various components of the shade device.
Other proposals have been made for assembling various complicated devices somewhat similar to the shade device described above. For example, U.S. Pat. No. 3,384,519 (Froget), discloses a method and machine for producing a continuous cloth comprising a series of strips secured between spaced vertical sheets. The machine includes heat welding units for securing each strip at its edge to one of the vertical sheets. Another embodiment of the machine includes two heat welding devices for securing both edges of the strip to opposing vertical sheets. The machine also includes two laterally movable clamps that pull the strip laterally into position adjacent an intermittently advancing sheet forming one of the vertical sheets.
U.S. Pat. No. 2,895,534 (Steidinger), discloses a mechanism for adhering gummed tape to the top flaps of envelopes. The tape is advanced by a single pair of drive rollers that impart a fold along the tape to give it some rigidity. The tape is held in position to be heat welded to the envelope flap by spaced vertically arranged guides which are retractable below the bottom pressure receiving surface of a heat welding device.
U.S. Pat. No. 2,714,413 (Hunter et al) discloses a method and apparatus for making plastic venetian blind ladders in which the plastic ladder tape is formed on a continuously advancing stainless steel belt. The tape is reinforced with threads of filaments, each fed from one cone in a series over an idler roller arranged in a vertical array of idler rollers. The respective top and bottom tapes are fed into spaced parallel relation and the blind support pieces are fused therebetween.